This work presents the characterization of the flow in a centrifugal separator. The study is focused on the behavior of the liquid phase in this kind of equipment, so that only single-phase liquid flow at the inlet of the separator is considered. The parameters investigated are the film thickness, the flow velocity components, the flow streamlines angles and the liquid level height above the inlet. These quantities were assessed for different flow rates using numerical simulations and experimental measurements. Results show that an increase on the inlet flow rate causes an increase on the liquid film thickness and the liquid level height. Also, the centrifugal movement is intensified when the flow rate increases. The numerical results proved to describe the overall flow behavior satisfactorily when compared to the experiments. From the outcomes of this study, information can be extracted to understand the separation process in this type of separator. (C) 2016 American Institute of Chemical Engineers